text: # Copyright 2016 The TensorFlow Authors. All Rights Reserved.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  # ==============================================================================
  """Tests for DecodePngOp."""
  
  from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import image_ops
  import tensorflow.python.ops.nn_grad  # pylint: disable=unused-import
  from tensorflow.python.platform import test
  
  
  class DecodePngOpTest(test.TestCase):
  
    def test16bit(self):
      img_bytes = [[0, 255], [1024, 1024 + 255]]
      # Encoded PNG bytes resulting from encoding the above img_bytes
      # using go's image/png encoder.
      encoded_bytes = [
          137, 80, 78, 71, 13, 10, 26, 10, 0, 0, 0, 13, 73, 72, 68, 82, 0, 0, 0,
          2, 0, 0, 0, 2, 16, 0, 0, 0, 0, 7, 77, 142, 187, 0, 0, 0, 21, 73, 68, 65,
          84, 120, 156, 98, 98, 96, 96, 248, 207, 194, 2, 36, 1, 1, 0, 0, 255,
          255, 6, 60, 1, 10, 68, 160, 26, 131, 0, 0, 0, 0, 73, 69, 78, 68, 174,
          66, 96, 130
      ]
  
      byte_string = bytes(bytearray(encoded_bytes))
      img_in = constant_op.constant(byte_string, dtype=dtypes.string)
      decode = array_ops.squeeze(
          image_ops.decode_png(
              img_in, dtype=dtypes.uint16))
  
      with self.test_session():
        decoded = decode.eval()
        self.assertAllEqual(decoded, img_bytes)
  
  
  if __name__ == "__main__":
    test.main()
  